Magnesium Oxide Board (or MgO Board) is a technologically advanced building material that offers superior performance in every category when compared to traditional wood, gypsum and cement based products. Magnesium Oxide Board is virtually impervious to fire, water, insects; does not feed mold or mildew; is non-toxic, non- flammable and non-combustible; is durable, maintains its dimensional stability-even when wet; and, has exceptional bonding surface. Magnesium Oxide Board is a mineral based green builder product. And it is homogeneous-no de-lamination. Features: WATER RESISTANCE Magnesium oxide inherently has very low water absorption and any moisture is naturally expelled. There is also no deterioration from freeze/thaw cycles. VERSATILITY Whether used on its own as a sheathing, wallboard or underlayment, or in conjunction with other building materials such as plywood, OSB or drywall, it can add tremendous value. MgO has an unlimited number of uses. Fire retardant plywood and OSB, demising walls and insulated exterior wall panels are some of the initial products that offer enormous performance-to-value propositions. FIRE RESISTANCE Magnesium oxide boards are essentially non combustible, with a flame spread of ZERO and a smoke development of ZERO.These properties make it highly effective either standing alone as a sheathing/underlayment or when laminated to other materials. IMPACT RESISTANCE While having the appearance and texture of cement or stone, magnesium oxide board has excellent flexure and tensile properties. All of these properties combine to produce a board with vastly superior impact resistance. Item Index Unites Density 0.9-1.2 g/cm³ Flexural strength â?¥14 Mpa Absorb water saturated flexural strength â?¥16 Mpa Moisture Movement â?¤0.30 % Thermal movement â?¤0.02 % Combustibility Incombustible class A Content of chlorine